Now we use 64-bits comparsion in MacroAssembler::string_equals, we can use neon instructions to improve the intrinsic's performance.

// Compare Strings

// For Strings we're passed the address of the first characters in a1
// and a2 and the length in cnt1.
// elem_size is the element size in bytes: either 1 or 2.
// There are two implementations. For arrays >= 8 bytes, all
// comparisons (including the final one, which may overlap) are
// performed 8 bytes at a time. For strings < 8 bytes, we compare a
// halfword, then a short, and then a byte.

void MacroAssembler::string_equals(Register a1, Register a2,
                                   Register result, Register cnt1, int elem_size)